1. Field of the Invention
This invention relates to a composite device, composite device system, method of controlling a composite device, and medium on which a program for controlling a composite device is recorded, and more particularly to such a composite device which comprises at least two devices and in which at least one of the devices controls the other, such a composite device system, such a method of controlling a composite device, and such a medium on which a program for controlling a composite device is recorded.
2. Description of the Prior Art
There has recently been a trend of standardizing connection of a computer with various peripheral devices such as printers, scanners, facsimile machines and digital cameras by the interface of the same connector and cable. This interface has been actualized by the universal serial bus (USB). The USB has specifications that a single computer can be connected to up to 127 peripheral devices. When a hub to which a USB device is connectable is provided, a plurality of peripheral devices can be connected through the hub.
When a plurality of functions are given to a single peripheral device, for example, when a composite device is realized by incorporating, into a peripheral device having only one connector connecting section for USB, a printer and a scanner both of which use a common printing mechanism, as devices, there is no means for carrying out exclusion between the devices. Accordingly, the devices need to be controlled individually in order that exclusion may be carried out for a common section such as the printing mechanism. More specifically, a user of the aforesaid composite device needs to use a predetermined one device while taking the other device into consideration. More concretely, when desiring to use the printer, the user needs to use it after having confirmed that the scanner is not used. In the same way, when desiring to use the scanner, the user needs to use it after having confirmed that the printer is not used. Furthermore, the composite device needs to be provided with means for displaying that individual devices have been incorporated therein. Thus, the same result is achieved as that in the case where a plurality of devices are merely connected together and accordingly, the advantages of the composite device cannot be obtained.
The present invention was made in view of the foregoing and an object of the invention is to provide a composite device which comprises at least two devices and in which at least one of the devices controls the other, so that the composite device can easily be operated since the user is conscious of only the device to be controlled without taking the other device into consideration, and in which competition between the devices can be eliminated, such a composite device system, such a method of controlling a composite device, and such a medium on which a program for controlling a composite device is recorded.
To achieve the object, the invention in one embodiment provides a composite device comprising an interface unit divided into at least two logical channels which are physically identical and obtaining a predetermined command, and at least two devices interconnected to the logical channels of the interface unit respectively and operated on the basis of the predetermined command, wherein at least one of the devices is a control device controlling an operation of the other device.
In the embodiment of the invention constructed as described above, the composite device includes two devices accomplish two predetermined functions respectively. One of the devices is a control device, and an operation accomplishing the function of the other device is controlled by the control device. The control of the operation of the other device by the control device includes, for example, a case where when the other device comprises a scanner, it is started, the scanning is performed, a predetermined setting is performed for the scanner, or status information delivered by the scanner is monitored. Furthermore, these at least two devices are physically identical, and the devices and the logical channels are connected by the interface unit divided into at least two logical channels respectively. More specifically, the device is connected to one of logically divided logical channels whereas the control device is connected to the other. The operation of the other device is controlled by the control device.
To be physically identical means that types of connectors and cables used for connection are the same and are connected to a single external device. A plurality of devices can be connected to the physically identical external device by a plurality of logical channels. The interface unit has the physically identical arrangement as described above and is connected to one external device. The interface unit is further divided into at least two logic channels for each of which a device is connected. Each device inputs a predetermined command from the external device to carry out a predetermined operation. The control device inputs a command for operating itself from the external device and a command for operating the other device. When inputting the command for operating itself, the control device carries out the predetermined operation. In the case of the command for the other device, the control device controls the operation of the device corresponding to the command. The single external device connected to the interface unit may be a computer which is connected to the composite device or a hub.
When the hub is connected as the external device, a plurality of external devices such as a computer are connectable. Accordingly, the command the interface unit inputs is a command delivered from the computer connected as described above or a command delivered from a plurality of computers connected via the hub or from an external device with a same host function as a computer.
As the device other than the control device, a device for obtaining image data or a device performing printing on the basis of image data is exemplified. In this case, the device for obtaining the image data may obtain the image data by a predetermined technique. For example, it may be a scanner. Of course, the device should not be limited to the scanner. It may be an image data file to be scanned by the scanner or image input from a digital camera or digital video.
The device carrying out the printing may be one which can print image data with a predetermined format or print data on a recording medium. Accordingly, the device may be a page printer or dot impact printer. Of course, it should not be limited to them and may be an ink jet printer.
On the other hand, two or more devices may be provided when the interface unit has two or more logical channels. For example, a plurality of devices such as a scanner, printer, digital camera or facsimile machine may be connected to the logical channels respectively.
The control device may control the operation of the other device by a predetermined hardware arrangement or processing on software. Of course, both of hardware and software may be used for the operation control.
A plurality of logical channels need to be set in the interface unit and external devices need to be connected to the respective logical channels and to be operated. Accordingly, the interface may be realized by USB or small computer system interface, SCSI. Of course, the interface unit need not be limited to these arrangements.
The control device controls the operation of the other device. In this case, the command for carrying out the operation and annexed data needs to be transferred to the other device. The command and data can be transferred via the logical channel between the devices. Even so, it is not advantageous on the processing for the interface unit performing data transfer from and to the outside to also perform data transfer in the composite device. In view of this problem, a further embodiment of the invention is constructed so that in the composite device, the control device secures a data transfer path to the other device and controls data transfer from said other device.
In the embodiment of the invention constructed as described above, the data transfer path is connected to both the control device and the other device. Accordingly, data can be transferred between the devices via the data transfer path. The control device carries out the data transfer.
When the command the control device inputs via the logical channel of the interface unit is used to operate the other device, the command is transferred via the data transfer path to the corresponding device together with data accompanying the command, so that the device is operated. Furthermore, data produced as the result of the operation of the device is input via the data transfer path. Furthermore, when the other device is provided and data transmission and date transfer is performed between the devices, the control device controls the data transfer between the devices.
Furthermore, another embodiment of the invention is constructed so that in the composite device, the device other than the control device includes at least a data input device and a data output device, and the control device controls data transfer between the data input and output devices.
In the embodiment of the invention constructed as described above, the device other than the control device comprises at least the data input device and data output device. The control device controls data transfer via the data transfer path between the data input and output devices. More specifically, data input by the data input device can directly be transferred to the output device via the data transfer path.
Furthermore, in yet another embodiment, the invention is constructed so that in the composite device, the control device includes a user interface unit directly receiving instructions from a user as well as said interface unit.
In the embodiment of the invention constructed as described above, the control device includes the user interface unit and receives instructions from the user via the user interface unit, controlling the other device on the basis of the instructions. More specifically, the control device can directly receive instructions about the operation of the device from the user as well as the interface unit.
When the control device inputs via the interface unit a plurality of commands operating one and the same device, namely, when a conflict occurs between commands, it is desirable that the control device can perform an exclusion control so that one of the commands operates the device. Furthermore, an external device needs to re-deliver the command when the command is cancelled as the result of the exclusion control. This is troublesome in the processing. In view of this problem, in another embodiment, the invention is constructed so that in the composite device, the control device inputs a predetermined command the interface unit has obtained and includes a command holding unit operating the device on the basis of one command while holding the other command, when a conflict occurs in the device to be operated on the basis of the predetermined command, the control device operating the device on the basis of the command held by the command holding unit upon completion of the operation on the basis of said one command.
In the embodiment of the invention constructed as described above, a conflict of operation occurs in the device when the control device inputs from the interface unit a plurality of commands operating one and the same device. The control device controls the device so that it is operated on the basis of a predetermined one of the commands in a conflict. In this case, the command holding unit sequentially holds the command which is not executed as the result of control. Upon completion of the operation on the basis of the predetermined command, the device is controlled so as to be operated on the basis of the command held by the command holding unit.
When a conflict occurs between operations of the device, the operation on the basis of the command held by the command holding unit is on standby. In this case, a cause for inexecution of the command is unknown at the side of an external device to which the command is delivered. This results in inconvenience. In view of this problem, one embodiment of the invention is constructed so that in the composite device, the control device includes an operation standby notifying unit notifying operation standby to the device to which the command held by the command holding unit is delivered.
In the embodiment of the invention constructed as described above, the operation standby notifying unit notifies operation standby to the device to which the command held by the command holding unit is delivered. Commands the composite device inputs at the interface unit include those which are used to operate the device and those which are used to obtain the status of the device. Accordingly, when a command is used to obtain the status of the device, the control device obtains a predetermined status of the device and notifies it to the device to which the command is delivered.
Accordingly, in another embodiment, the invention is constructed so that in the composite device, the control device includes a status notifying unit obtaining, from the device, a status indicative of a working condition of the device, when the command obtained by the interface unit is a command for obtaining a status.
In the embodiment of the invention constructed as described above, the control device obtains a status indicative of a working condition from the device via the data transfer path when a command obtained by the interface unit is used to obtain a status of the device. The control device further notifies the status via the logical channel to an external device to which the command is delivered.
In one embodiment using the composite device, a predetermined device is operated on the basis of a command obtained by the interface unit and data attendant on the command, so that a desired output is achieved. Even so, the same importance is not put on all of a plurality of commands. They include important commands or commands having priority over others and less important commands or commands having no priority over others. When a command having a higher importance and operating a device is obtained while the same device is being operated on the basis of another command having a lower importance, it is desirable that the command in execution is interrupted and the obtained command having the higher importance is executed.
Accordingly, in another embodiment, the invention is constructed so that in the composite device, the control device includes a priority setting unit setting a priority for commands obtained by the interface unit, and when inputting a command operating a predetermined device and having a higher priority while operating the predetermined device on the basis of another command having a lower priority, the control device interrupts operation of the device on the basis of the command having the lower priority and operates the device on the basis of the command having the higher priority.
In the embodiment of the invention constructed as described above, the control device includes a priority setting unit setting a priority for commands obtained by the interface unit. When inputting a command operating a predetermined device and having a higher priority while operating the predetermined device on the basis of another command having a lower priority, the control device interrupts operation of the device on the basis of the command having the lower priority and operates the device on the basis of the command having the higher priority.
When the command having the higher priority is accepted and execution of the command having the lower priority is interrupted, the command needs to be re-input regarding the interrupted one. This could cause problems. In view of this problem, one embodiment of the invention is constructed so that in the composite, the control device holds in the command holding unit the command regarding which the operation of the device is interrupted and operates the device on the basis of the command regarding which the operation of the device is interrupted, said command being held by the command holding unit, when the operation of the device on the basis of the command having the higher priority.
In the embodiment of the invention constructed as described above, the control device holds the interrupted command at the command holding unit and operates the device on the basis of the interrupted command upon completion of execution of the command having the higher priority.
The aforesaid composite device may exist as a single substance or may be a composite device system composed by connecting the composite device to a host delivering predetermined commands and data attendant on the commands to the interface unit. Accordingly, another embodiment of the invention provides a composite device system including a host delivering a predetermined command and a composite device connected to the host, including a plurality of devices, and inputting the command delivered by the host to thereby operate a predetermined device on the basis of the command, the composite device comprising an interface unit divided into at least two logical channels which are physically identical and obtaining a predetermined command, and at least two devices interconnected to the logical channels of the interface unit respectively and operated on the basis of the predetermined command, wherein at least one of the devices is a control device controlling an operation of the other device, and wherein the host includes a command output unit delivering a predetermined command.
In the embodiment of the invention constructed as described above, the composite device system includes a host generating and outwardly transferring a command and data attendant on the command, and a composite device inputting the command and data attendant on the command and operating a device corresponding to the command. The host and the composite device may be connected together in the relation of one-to-one or a plurality of hosts and a plurality of composite devices may be connected optionally. The composite device obtains at the interface unit a predetermined command. When inputting the command obtained by the interface unit, the control device controls the other device on the basis of the command. On the other hand, the host generates in the command output unit a predetermined command. The command is delivered to the interface unit of the composite device connected to the host.
A technique for controlling at least two devices connected to at least two logical channels respectively should not be limited to a substantial device and it can easily be understood that the technique may function as a method. Accordingly, in yet another embodiment, the invention provides a method of controlling a composite device controlling at least two devices connected to at least two logical channels respectively, comprising an interface step of obtaining predetermined commands from at least two logical channels which are physically identical, and a device operating step of operating said at least devices connected to said at least two logical channels respectively, on the basis of the predetermined commands, wherein an operation of at least one device is controlled by the other device.
Thus, the technique should not be limited to the substantial device and must be effective as a method. By the way, the composite device controlling at least two devices connected to at least two logical channels respectively sometimes exists independently or are sometimes used as incorporated in another device. Thus, the scope of the invention covers various forms of implementation. Accordingly, the invention may be implemented as software or hardware.
When the present invention is implemented as software for a copier performing copying and printing on the basis of obtained predetermined print data while storing image data obtained by a predetermined technique, the invention exists as a recording medium on which the software is recorded. As one example, in a further embodiment, the invention provides a medium on which a composite device control program for controlling at least two devices connected to at least two logical channels respectively, the program performing an interface step of obtaining predetermined commands from at least two logical channels which are physically identical, and a device operating step of operating said at least devices connected to said at least two logical channels respectively, on the basis of the predetermined commands, wherein an operation of at least one device is controlled by the other device.
The recording medium may be a magnetic one or a photomagnetic one, or any recording medium that will be developed in the future. Furthermore, the invention may take such a replicated form as a primary replicated product, secondary replicated product, etc. In addition, the invention may be supplied through use of a communication line.
Furthermore, there may be provided such an arrangement that some parts of the present invention are embodied in software while the other parts thereof are embodied in hardware. In a modified embodiment of the invention, some parts thereof may be formed as software recorded on a storage medium to be read into hardware as required.